Overview
AISI 347 stainless steel is a versatile and high-performance material widely used in various industries for its excellent mechanical properties and resistance to corrosion. It is a columbium-stabilized austenitic stainless steel with a unique composition that enhances its performance in high-temperature environments.
AISI 347 stainless steel is often chosen for applications that require prolonged exposure to high temperatures because it offers superior resistance to intergranular corrosion. In this comprehensive guide, we will explore the specifics of AISI 347 stainless steel, including its composition, properties, applications, and more.
Composition of AISI 347 Stainless Steel
The composition of AISI 347 stainless steel plays a critical role in its performance. Here is a detailed breakdown of its chemical makeup:
| Element | Percentage |
|---|---|
| Chromium (Cr) | 17-19 |
| Nickel (Ni) | 9-12 |
| Carbon (C) | 0.08 max |
| Manganese (Mn) | 2.0 max |
| Silicon (Si) | 1.0 max |
| Phosphorus (P) | 0.045 max |
| Sulfur (S) | 0.03 max |
| Columbium (Cb) | 10 x C min |
| Iron (Fe) | Balance |
Properties and Characteristics
AISI 347 stainless steel boasts a unique combination of mechanical and chemical properties:
- Corrosion Resistance: Excellent, especially in environments exposed to high temperatures.
- Tensile Strength: Approximately 515 MPa (75 ksi).
- Yield Strength: Approximately 205 MPa (30 ksi).
- Elongation: 40% in 50 mm.
- Hardness: Brinell hardness of 201.
Applications of AISI 347 Stainless Steel
AISI 347 stainless steel is used in various applications due to its ability to withstand high temperatures and resist corrosion. Some of the primary applications include:
| Application | Description |
|---|---|
| Aerospace Components | Ideal for parts exposed to high temperatures. |
| Chemical Processing Equipment | Used in tanks, pipes, and heat exchangers due to its corrosion resistance. |
| Power Generation | Employed in turbine blades and other components in power plants. |
| Food Processing | Utilized in equipment that requires sanitation and durability. |
| Oil and Gas | Suitable for pipelines and offshore platforms. |
| Pharmaceuticals | Applied in equipment where contamination prevention is critical. |
| Automotive Exhaust Systems | Used for parts that must withstand high heat and corrosive gases. |
Specifications, Sizes, Grades, and Standards
AISI 347 stainless steel is available in various sizes and grades, making it versatile for different applications. Here’s a table outlining common specifications:
| Specification | Details |
|---|---|
| ASTM A240 | Standard for chromium and chromium-nickel stainless steel. |
| ASTM A312 | Standard specification for seamless, welded, and heavily cold worked austenitic stainless steel pipes. |
| ASTM A403 | Standard for wrought austenitic stainless steel fittings. |
| Sheet Thickness | 0.1mm to 4mm |
| Plate Thickness | 4mm to 100mm |
| Pipe Diameter | 0.5 inch to 24 inches |
| Bar Diameter | 1mm to 500mm |
Suppliers and Pricing
Pricing for AISI 347 stainless steel can vary based on market conditions, quantity, and specific requirements. Here is an overview of typical suppliers and price ranges:
| Supplier | Product | Price Range (USD) |
|---|---|---|
| Company A | Sheets and Plates | $3 – $5 per kg |
| Company B | Pipes and Tubes | $4 – $6 per kg |
| Company C | Bars and Rods | $3.5 – $6.5 per kg |
| Company D | Customized Components | $5 – $8 per kg |
Pros and Cons of AISI 347 Stainless Steel
Understanding the advantages and limitations of AISI 347 stainless steel helps in making informed decisions for specific applications. Here’s a detailed comparison:
| Aspect | Advantages | Disadvantages |
|---|---|---|
| Corrosion Resistance | Excellent in high-temperature environments | Less effective in low temperatures |
| Mechanical Properties | High tensile and yield strength | Relatively high cost compared to other steels |
| Temperature Stability | Maintains strength at high temperatures | Can be difficult to machine |
| Weldability | Good weldability | Requires preheating and post-weld treatments |
Metal Powder Models of AISI 347 Stainless Steel
In the realm of metal powders for additive manufacturing and other applications, AISI 347 stainless steel is available in various models, each tailored for specific uses. Here are ten notable metal powder models:
- AISI 347-LP (Low-Particle)
- Optimized for high-resolution printing with minimal particle size.
- AISI 347-HP (High-Performance)
- Enhanced mechanical properties for demanding applications.
- AISI 347-CF (Corrosion-Resistant Fine)
- Ideal for environments requiring fine detailing and high corrosion resistance.
- AISI 347-AP (Additive Printing)
- Specifically designed for 3D printing and additive manufacturing.
- AISI 347-TF (Thermal Fatigue Resistant)
- Engineered to withstand thermal cycling and fatigue.
- AISI 347-SP (Surface Polished)
- Provides a superior finish for applications requiring smooth surfaces.
- AISI 347-WP (Wear-Resistant Powder)
- Enhanced wear resistance for parts subjected to friction.
- AISI 347-HT (High Temperature)
- Optimal performance at elevated temperatures.
- AISI 347-MP (Multi-Purpose)
- Versatile powder suitable for a range of applications.
- AISI 347-FG (Fine Grain)
- Ensures fine grain structure for precise manufacturing.
Advantages of AISI 347 Stainless Steel
AISI 347 stainless steel offers numerous benefits that make it a preferred choice in various industries:
Corrosion Resistance
One of the standout features of AISI 347 stainless steel is its excellent corrosion resistance, particularly in environments where high temperatures are a factor. This makes it ideal for chemical processing, power generation, and aerospace applications.
High Temperature Stability
AISI 347 maintains its strength and structural integrity at elevated temperatures, making it suitable for use in high-temperature environments like turbine engines and exhaust systems.
Mechanical Strength
The mechanical properties of AISI 347, including its tensile strength and yield strength, are impressive. This makes it a reliable choice for applications requiring robust and durable materials.
Versatility
With its wide range of forms (sheets, plates, pipes, bars), AISI 347 can be used in various industries, from aerospace to pharmaceuticals. Its versatility ensures it can meet the demands of different applications effectively.
Disadvantages of AISI 347 Stainless Steel
Despite its numerous advantages, AISI 347 stainless steel does have some limitations:
Cost
AISI 347 is relatively expensive compared to other stainless steels. This higher cost can be a factor in budget-sensitive projects.
Machinability
The material can be difficult to machine, requiring specialized equipment and techniques. This can add to the overall cost and complexity of manufacturing processes.
Limited Low-Temperature Performance
While AISI 347 excels in high-temperature environments, its performance in low-temperature settings is less impressive. This limitation can restrict its use in certain applications.
Comparison of AISI 347 Stainless Steel with Other Grades
Comparing AISI 347 with other stainless steel grades helps in understanding its unique position in the market:
| Property | AISI 347 | AISI 304 | AISI 316 | AISI 321 |
|---|---|---|---|---|
| Corrosion Resistance | Excellent (high temp) | Good | Excellent (general) | Good (high temp) |
| Tensile Strength | 515 MPa | 505 MPa | 515 MPa | 515 MPa |
| Yield Strength | 205 MPa | 215 MPa | 240 MPa | 205 MPa |
| Temperature Resistance | Excellent (up to 800°C) | Moderate (up to 500°C) | Good (up to 600°C) | Excellent (up to 800°C) |
| Cost | High | Moderate | High | High |
FAQ
What is AISI 347 stainless steel?
AISI 347 (also known as UNS S34700) is a type of austenitic stainless steel formulated for use in wrought products (products shaped by hammering, pressing, or rolling). It’s known for its resistance to a phenomenon called weld decay, which can weaken other types of stainless steel at high temperatures [ONSULT MakeItFrom.com].
What are the key properties of AISI 347?
- Good high-temperature strength: AISI 347 maintains its strength even at elevated temperatures, making it suitable for applications like boilers and furnace parts.
- Resists weld decay: The inclusion of niobium (Nb) in its composition prevents chromium carbide precipitation near welds, which can cause weakness in other stainless steels [ONSULT Online Metals].
- Good corrosion resistance: Like other stainless steels, AISI 347 offers good resistance to corrosion.
- Ductile and workable: It can be easily formed and shaped.
What are some applications of AISI 347?
- Aircraft exhaust systems
- Boiler casings and heat exchangers
- Heaters and furnace components
- Welding equipment
- Chemical processing equipment [ONSULT Online Metals]
What are some things to consider when using AISI 347?
- While it offers good corrosion resistance, it may not be suitable for all corrosive environments. Consult with a material specialist for specific applications.
- AISI 347 is not magnetic.
- It is considered moderately machinable.
